Types of contaminants that affect compressed air systems

We all know how important the quality of compressed air is. You need to achieve a certain level of quality to use your compressed air for some applications. And achieving different levels of compressed air quality is only possible with the right systems. 

Unfortunately, regardless of the quality you need and the system you use, a compressed air network is open to all kinds of contaminants. There are four main sources of contamination: 

1. Water or vapour air drawn in with the atmospheric air
2. Oil within air compressor
3. Dust and other particles
4. Rust

With filters, cleaning and regular maintenance, you’re able to minimise the chance of your compressed air becoming contaminated. But fail to do it and you risk all kinds of problems.

In this article you will learn about:

• Compressed air contamination from water
• Compressed air contamination from oil
• Compressed air contamination from dirt, dust, and other particles
• Rust

Would you believe it? About 99.9% of all the contaminations in compressed air systems are caused by water. It covertly infiltrates your system under the cover of atmospheric air and doesn’t take long to start causing problems.

Whether it’s in the form of vapour or condensation, water is horribly destructive. It will give you all kinds of problems ranging from corrosion and reduced tool performance to increased maintenance costs, greater air leakage, problems in control systems and instruments, and of course, plenty of potential for growing mould and bacteria you would probably prefer to go without. 

You can prevent contaminants from water with regular maintenance, including the replacement of your filters and regular draining of your air dryer. We offer also specific drainers to get rid of the excessive water. 

It’s never particularly pleasant to have water in your air compressor system. What about oil? You may need it in your system. However, you just want to avoid the compressed air contamination from oil.

As with water, traces of oil in the atmospheric air can be drawn in by your compressor. The oil will form a vapour or aerosol in your compressed air, or condense it back into a liquid state. It can even mix with water to form an acidic condensate.

Even few drops of oil can damage different parts of your compressed air system, affect production equipment and of course, contaminate your compressed air. This is why businesses such as food or medical applications need oil-free compressors, which don’t use any lubricant.

The answer is regular maintenance. We generally wouldn’t recommend switching to a non-oil-lubricated system unless you need very-high-quality compressed air or a particularly low oil content for several reasons. Among all, the cost of a oil.-free compressors is much higher and it actually requires even more maintenance than a standard system. 

How large do you think a typical dirt or dust particle is? If you think it’s big, you’re in luck; anything larger than two microns will typically be picked up by your different air filters. After all, this is their function. Your air filters stop all these devious particles from sneaking into your compressor and making their way through your compressed air piping system and into your products. 

The only problem is the other little dirt and dust particles. If particles are smaller than two microns, there’s a good chance they’ll find their way through the filters. They’ll eventually bump into each other, merge into bigger particles and create more drastic blockages in your system. These blockages have the potential to affect the functioning of your tools, cause damage and create even more opportunities for water and oil to congregate.

Once in the system, particles can sneak into your products too. Depending on what you’re working on or producing, you’ll probably end up with great issues and a huge headache. 

To prevent contaminations from dust or other particles you need specific filters and regular maintenance. Their combination will help you cleaning of your air compressor, especially around the air-inlet valve.

The location of you compressor plays a crucial role to keep it clean. If your compressor is outside, you might consider building walls around it. If it’s installed inside your production building, you might have to move your machine to a place where it’s exposed to less dirt and dust. 

Remember all the water vapour and condensation from earlier? They are nothing if compared to create rust. And rust is a chemical reaction that spread quickly. It will sneak under the coating on the inside of your pipes and do its best to make that coating flake off. In other words, it will ruin your compressed air network very quickly.

To avoid possible issues, you need to use the right filters, clean and replace them frequently, and regularly check for signs of rust in your compressed air network. If you find some, be prepared to eventually replace whichever part of the network you’ve found it in.

During the compression process, moisture is drawn in with ambient air in the form of water vapor. As the air cools, the vapor condenses into liquid water.

Common contaminants include water vapor, oil, particulates, and microorganisms. The sources vary from ambient air, lubricants, and the system itself.

One of the most common questions to ask when it comes to compressed air contamination is ‘How bad is it?’. This will depend on how you use your air compressor and compressed air network. A little rust here or there may not be an immediate problem. A touch of dust and dirt is understandable if you’re based on the beach, so you need to be prepared to clean your machine more frequently. The degree of problems you’ll face due to compressed air contamination depends on what you use your system for.

Do you want more information about your specific contamination situation? Get in touch with our experts. We will gladly discuss your situation with you, offer you advice and any other form of assistance.